Dithiocarbonic anhydride (CS2)—a new additive in Li-ion battery electrolytes

Dithiocarbonic anhydride (CS 2 ) was evaluated as an additive to electrolytes in Li-ion rechargeable batteries. Graphite electrodes, polarized versus Li metal, can undergo reversible intercalation–deintercalation processes in diethyl carbonate (DEC)+1 M LiPF 6 electrolytes containing CS 2 as an additive. It was found that the use of CS 2 as a passive film formation agent on the graphite anode surface is more powerful than the use of carbon dioxide (CO 2 ) as an additive in DEC electrolytes. On the other hand, we found that CS 2 is less dominant, as a surface film formation agent, than SO 2 . Cyclic voltammetry and chronopotentiometric methods were used in order to understand the reaction mechanism better. A methodology employing DEC is proposed to evaluate new electrolyte formulations for Li and Li-ion batteries quickly and conveniently.